68kMLA Classic Interface

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Macintosh SE & External BlueScsi Power Delivery?
Posted by: Marsu on 2023-02-21 12:40:00
I have an External Blue SCSI. When used with my Macintosh SE FDHD Model 5011, the SCSI device works perfectly fine without the need for a micro usb power source.

With my Macintosh SE Model 5010, The device only works if I power it with a micro usb cable. I thought this only applied to the Plus or other models not part of the "compatibility list" provided on the GitHub page.

Questions are
1) Is there a difference between models when it comes to external SCSI power delivery
2) If question 1 is a no. Could this 5010 have some mainboard issue with it comes to power delivery to the external SCSI port
Posted by: ronservice on 2023-03-13 01:44:18
I too am having trouble with my new BlueSCSI V1getting no power from either of my two Macintosh SE's. I have to use USB power for the thing to fire up. I have a 5010 and a 5011 model SE's - same thing for both.
Posted by: Marsu on 2023-03-13 08:45:40
I too am having trouble with my new BlueSCSI V1getting no power from either of my two Macintosh SE's. I have to use USB power for the thing to fire up. I have a 5010 and a 5011 model SE's - same thing for both.
The only thing i figured out was the the 5010 model did need external power through the microUSB ports and all of my 5011 models worked independently without external power.
Posted by: jmacz on 2023-03-13 10:39:18
I'm not using a BlueSCSI, but just an fyi (not sure if this helps you). I have a Macintosh SE (model 5010) and it is delivering power to my internal ZuluSCSI via the SCSI cable. It also delivers power to an external ZuluSCSI device as well (via the 25 pin connector). So the 5010 is capable of delivering power via the scsi connectors.
Posted by: dochilli on 2023-03-14 01:05:15
Did you measure the voltages? Perhaps they are lower at the 5010?
Is the AB recapped?
Posted by: joshc on 2023-03-14 04:04:18
Measuring voltages is a good shout, the power supply may need to be recapped. The AB shouldn't affect it.
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